A perfume atomiser is a perfume bottle with a bulb at the end. To spray the perfume, you must squeeze the bulb. Most perfume atomisers are antiques and very collectable. Even if the atomiser in question is not antique, it is a lovely display item that also has a practical use. If something happens to your perfume atomiser's bulb, it can be replaced.
Remove the old bulb from the perfume atomiser. It either screws off or slips off, depending on the type of bulb.
Screw the new bulb onto the end of the atomiser's tube if it is a screw-on bulb type atomiser.
Slip the tube onto the end of the atomisers tube if it is a slip-on bulb type.